source: orxonox.OLD/branches/resources/src/lib/util/loading/resource.h @ 7229

/*!
 * @file resource.h
 * @brief Definition of a Resource.
*/

#ifndef _RESOURCE_H
#define _RESOURCE_H

#include "base_object.h"
#include "multi_type.h"
#include <string>
#include <map>
#include <vector>


namespace Loading
{
  // FORWARD DECLARATION

  //! An enumerator for different (UN)LOAD-types.
  /**
   * RP_NO:        will be unloaded on request
   * RP_LEVEL:     will be unloaded at the end of a Level
   * RP_CAMPAIGN:  will be unloaded at the end of a Campaign
   * RP_GAME:      will be unloaded at the end of the whole Game (when closing orxonox)
   */
  typedef enum ResourcePriority
  {
    RP_NO        =   0,
    RP_LEVEL     =   1,
    RP_CAMPAIGN  =   2,
    RP_GAME      =   3
  };


  //! A Resource is an Object, that can be loaded from Disk
  /**
   * A Resource can cahnge the internal type, meaning it is a
   * SmartPointer, that keeps track of the InternalCount of the
   * Resource (SharedResource).
   */
  class Resource : virtual public BaseObject
  {
  protected:
    /**
     * This is a Class for the internal handling of the Resource.
     * Any Resource keeps exactly one of these Classes, so it can
     * reference and move it around, and keep track of how many
     * references of it are stored.
     */
    class SharedResource
    {
    public:
      SharedResource();
      std::string       fileName;

      unsigned int      referenceCount;    //!< How many times this Resource has been loaded.
      ClassID           type;              //!< ResourceType of this Resource.
      ResourcePriority  prio;              //!< The Priority of this resource. (can only be increased, so noone else will delete this)

      MultiType         param[3];          //!< The Parameters given to this Resource.
    };


  public:
    Resource(const std::string& fileName = "", ResourcePriority prio = RP_LEVEL);
    virtual ~Resource();

    // looks if the resource was already loaded and (if not) loads it.
    virtual bool load(std::string& fileName = "",
                      ResourcePriority prio = RP_LEVEL,
                      const MultiType& param0 = MT_NULL,
                      const MultiType& param1 = MT_NULL,
                      const MultiType& param2 = MT_NULL);
    // reloads the resource.
    virtual bool reload() { };
    // unloads the sharedResource (from this Resource)
    virtual bool unload();

    // checks if a resource was already loaded.
    bool isLoaded(std::string& fileName,
                  const MultiType& param0 = MT_NULL,
                  const MultiType& param1 = MT_NULL,
                  const MultiType& param2 = MT_NULL);

    // raises the priority can only be raised
    void raisePriority(ResourcePriority prio);
    /** @returns the referenceCount of the shared resource behind this resource or 0 if no internal Resource is stored */
  unsigned int referenceCount() const { return (this->resource)? this->resource->referenceCount : 0; };

  protected:
    const SharedResource* findResource(std::string& fileName,
                                       const MultiType& param0 = MT_NULL,
                                       const MultiType& param1 = MT_NULL,
                                       const MultiType& param2 = MT_NULL);

  protected:
    SharedResource*     resource;          //!< The internal Resource, this Resource is keeping (at the moment).

    static std::map<ClassID, std::vector<SharedResource> > storedResources;
  };

}
#endif /* _RESOURCE_H */